Archive for the ‘Green Homes’ Category

The Cost of Energy

We all need it. We all use it. In fact, we use enormous amounts of it and, since the Industrial Revolution, we have mostly taken it for granted and thought little of how it got to us or how we used and/or wasted it.

The energy we use has a cost, and that cost goes far, far beyond the money we spend to buy it. Be it fossil fuels (coal, oil, natural gas) or nuclear power, this energy has cost us dearly. Aside from the climate change impacts of burning fossil fuels (whether you subscribe to this theory or not), there is also the staggering toll taken on our health and environment from the extraction (loss of habitats, ground and surface water contamination, loss of human lives as well as wildlife), processing (more of the same, plus the energy and water consumed) and burning (disease, cancer, deaths, air/water pollution, smog) of these fuels. While nuclear power doesn’t spew out much in the way of greenhouse gas emissions, the risks and implications of dealing with the radioactive spent fuel rods will endure for millennia. And this doesn’t even include the impacts of massive oil/fuel spills (not to mention the cumulative effect of millions of smaller ones every year) and nuclear disasters.

Add up all the tax money spent on environmental clean ups, health care and subsidies and the real price you pay for that energy goes way beyond the price per gallon or price per kilowatt-hour.

The dollars per unit of energy we pay are simply the monetary “costs”. We tend to have a misguided view that everything be seen in terms of economics and stock valuations, and this has been very destructive. Economic “growth” cannot continue in its current form, perpetually, at the expense of the environment we live in; we simply do not have the resources available to produce, consume and throw away the way we have without poisoning the entire planet, and in fairly short order. Think just in terms of what it’s all doing to our food and water supplies, as well as our air, and this issue should be of paramount concern to every person alive.

There are really only 3 ways to improve this situation:

       1.   Develop clean, renewable energy sources
             – This takes years. There are promising results, and more needs to be done more quickly, especially in North America, where we are way behind other countries.

      2.   Reduce consumption
             –
A relatively easy thing to accomplish, if we choose to, though human population growth makes total consumption difficult to keep in check. How many times do you see dozens, or hundreds, of lights on in an empty building at night? There are easily tens of millions of them every night around the world. Think how much energy could be saved and talk to the people who manage the building you work in.

      3.   Increase efficiency
             –
Probably the most effective way to decrease energy use quickly. Our homes and buildings consume nearly 50% of all energy used, most of which is for space heating/cooling and water heating. The opportunities are there to save enormous amounts of energy, and money, and in turn reduce environmental impacts.

No rational person will fool themselves into thinking fossil fuels and nuclear power will go away next year or even next decade. We can, and must, however, take a multitude of steps toward significantly reducing their use in the coming years while more quickly developing the alternatives that will eventually replace them. There has to be a very strong political and public will to do this, as well as a focus on looking beyond our immediate wants and needs, if this process is to accelerate enough to avert an almost inevitable global ecological disaster. In the grand scheme of things, making these changes will not cost us…it will save us.

A touch of doom and gloom? Perhaps; but maybe that’s exactly what’s needed to snap our collective minds to attention when it comes to our future.

Andrew W. Alcorn, CET
Innova Builders, Inc.
(902) 499-4839
www.innovabuilders.ca 
andrew@innovabuilders.ca

@InnovaBuilders on Twitter
Innova Builders on Facebook

Advertisements

Your house is a system

 All houses are not created equal – not by a long shot. Even houses of a similar size and style can, and sometimes should, have significant differences between them. Many of these differences are unseen or not obvious, but nonetheless important.

There are certainly no “one-size-fits-all” approaches as every building is different, as are its occupants and their preferences and budgets. To properly design a new home, or to plan major upgrades to an existing one, there are many things to consider and plan for: size and type, floor plan, lot layout, lot location, climate, soil conditions, orientation to the sun, the building’s integration into the land, foundation configuration, trees, shading, wind, grading and drainage, landscaping, water and sewer considerations, energy sources (geothermal, solar, electric, etc), insulation systems and thicknesses, plumbing, electrical, control systems, structural considerations, decks, water usage/conservation, interior/exterior materials, appliances, lighting, windows & doors, ventilation, heating/cooling, roof overhangs, roof pitch and configuration,…and, of course, the building envelope itself ( http://bit.ly/hL5bls ) and its proper design for the house/location. These items affect not just a home’s energy efficiency, but also its comfort and enjoyability, all of which ultimately affect its value.  

Each of the items in this list needs to be addressed in order to maximize free heat energy from the sun, ensure efficient use of energy and water, create good indoor comfort and air quality, and enjoy the whole property. What’s crucial to understand is that changing 1 or more of these items will often create a “domino-effect” across several areas of the project making it important to reassess the big picture. For example, a given house plan with a great view from the back will likely have you wanting more, and larger, windows there. Whether the back faces north or south will have a very large effect on choosing the types of windows to use, the size of them, the roof overhang, the flooring types in the rooms with these windows, use of thermal mass, the heating system capacity and type, roof configuration, possibilities for solar panel usage and even how you may decide to integrate hot-water heating.

Any builder worth investing your hard-earned money in (large amounts, I might add) will be able to do this intelligently and provide you with multiple options while answering all of your questions and helping you to understand the value of each one given your individual circumstances. If they can’t, or won’t (as someone I recently spoke to recounted from a meeting with a builder), then it’s time to change builders.

You get to do this once on a given house and then live with the results for sometimes many years, or even decades. Doing it right means treating your home and property as an integrated system whose parts work together to keep you comfortable, save you significant energy dollars every month and give you a durable home that will return the best value for your investment.

As always, your questions and comments are welcomed.

Andrew W. Alcorn, CET
Innova Builders, Inc.
(902) 499-4839
www.innovabuilders.ca 
andrew@innovabuilders.ca

@InnovaBuilders on Twitter
Innova Builders on Facebook

InnovaWall in action

Please view and share this video. It is a project using a base version of my InnovaWall system.

http://www.youtube.com/watch?v=pn7TqQgB-Ak

For a complete thermal break, sheets of rigid high-density insulation are placed between the studs and sheathing, instead of the horizontal 2x4s in the video, and then the spray foam is applied for a complete air/vapour seal and a high level of insulation. The total R value can be adjusted by using thicker rigid insulation and a 2×6 stud wall for up to an R45 wall system with no air leakage.

In fact, the insulation system for the whole house or building, including foundation, walls and ceiling, is customizable to suit conditions, usage and owner preference. That’s the beauty of the InnovaWall.

Andrew W. Alcorn, CET

Innova Builders, Inc.
www.innovabuilders.ca
andrew@innovabuilders.ca
@InnovaBuilders on Twitter
Innova Builders on Facebook

Batt Insulation….Exposed

We all know that insulation is important to keeping our homes and buildings warm in winter and cooler in summer. The most commonly used type of insulation is fibreglass batts that come in bags.

Is this fibreglass batt insulation effective? For the most part, no. The most critical aspect is if the insulation is properly installed and (here’s the kicker that’s often overlooked) that it is incorporated effectively into a wall or ceiling system. The fact that this insulation exists in your walls does not make it effective. In fact, an alarmingly high percentage of building envelopes (see my previous post on this) are not properly installed, making the insulation much less effective than the R-value of the product. More precisely, the biggest factor is air leakage and flow through the building envelope. Air leakage accounts for more heat loss than the effective R-value of insulation.

You can look at a bag of fibreglass batt insulation and it will tell you it is, for example, R20. In a lab, under ideal conditions, with no air flow and no moisture present, it will indeed perform at R20 – through the middle of a nice, perfectly fluffed-up batt. Exactly the kind of conditions that are almost NEVER found in the real world in an actual installation. In a real-life situation, batts are stuffed in tight spaces, pushed around pipes and wires, have gaps around the edges and end up inside a wall cavity that will have cold, damp air flowing into, around and through it. When batt insulations are compressed or encounter moisture (fog and high humidity anyone?) their effective R-value drops dramatically. Allow air to flow through or around them and the same thing happens – large drops in effective R-value.

Ahhh, but the modern “efficient” house is well air-sealed you say? And it has blower-door tests that prove the air-leakage is reduced? Let’s look at what, exactly, this tells us. Sure, the low air-leakage is a good thing, but what does the blower-door test really tell you? It tells you how much air is leaking past the air/vapour barrier. And where is this air/vapour barrier? In a typically constructed house, it’s up against the back of your drywall; yes THAT drywall that people will later poke holes through to hang picture frames, decorations, etc. So what it tells you is that only so much air gets past the drywall, however when you think about it, that means that cold air is flowing up against the drywall, creating heat loss. If it’s getting to the drywall, that means it has to go through and around the batt insulation, and we just talked about what that means – dramatically lowered effective R-values in your walls.

It is for the above reasons that I will not use fibreglass batt insulation in a building. It is an outdated, ineffective way to insulate a building and it is time we retired it.

In a future post, I’ll discuss other types of insulation and wall systems, including my InnovaWall System, and how they work.

Until next time.

Moving Toward Sustainability

Let’s be honest with ourselves. As Canadians, we consume many times more natural resources per-capita than every “less-developed” country. In fact, if every country in the world consumed as much as we did, we would require the equivalent of about 4 planet Earths to sustain everyone.

What is “sustainability”, anyway? CMHC defines it as “…an economic, social, and environmental concept that involves meeting the needs of the present without compromising the ability of future generations to meet their own needs.” Another source simplifies it as “the ability to endure.” Any way you slice it, we should expect of ourselves that each generation leaves the planet in such a condition that the next can prosper and survive.

Are we doing this? Quite frankly…no, we are not. And why is that? Part of it is greed and part of it is simply not thinking (or caring) about the long-term implications of our lifestyles. In Canada, resources have historically been relatively “cheap” for us. Who worried about how efficient their houses and offices were? No matter how you heated it, it was inexpensive to do so and the fuels were plentiful and easily accessible.

Enter the oil crisis of the 1970s, the Gulf War of the 1990s and the dot-com crash of the 2000s. Add in geopolitical instabilities in multiple areas of the world, an Exxon Valdez here and a Gulf of Mexico oil spill there and we have volatility that holds millions hostage to the prices of oil and natural gas – commodities that some would argue are past their heyday, and most would admit are harming our environment in a very big way.

But what’s a community/province/region/country to do? Well, you start by changing policies and people’s expectations of where they get their energy from. You start to educate as many businesses and homeowners as possible about the advantages of renewable energy, energy independence and, even more importantly, the value in reducing energy consumption. That’s where every homeowner, potential homeowner, business owner, landlord and anyone else with a building that consumes energy comes in. Our buildings use 40-50% of all energy consumed and, given that many are very inefficient, this offers one of the biggest opportunities for energy usage reduction out there. And, unlike global commodity markets, it’s opportunity that we have control over as individuals.

Whether through new construction or the upgrading of the millions of existing buildings that are enormous energy-wasters, we have the ability to significantly reduce energy consumption, and in turn greenhouse gas emissions, and save ourselves a ton of money in the process. It’s a real no-brainer when you take time to analyze the cost-benefit of doing this so let’s make a concerted effort to collectively move toward making all our buildings energy-efficient when it comes time to build or upgrade.

When I say energy-efficient, I mean truly efficient – so that means not falling for false promises and “greenwashed” products. It means moving away from “traditional” construction methods and using new products and better specifications for all buildings. Many of today’s claimed “efficient” homes use obsolete insulation systems, are poorly put together with little attention to important details and waste far more energy than they need to.

With a little research and effort, asking the right questions and seeing through the bogus claims, we can all do our part to help move our communities, and society in general, toward something sustainable that we can feel good about passing along to the next generation. I’ve made it my mission to help as many people and businesses as possible accomplish this and any time our efforts move us closer to a sustainable community, we can all feel a little bit better about the legacy we leave.

This is not just important…it is critical to our survival as a society.

All comments and questions are welcomed and encouraged.

Andrew W. Alcorn, CET

Innova Builders, Inc.
www.innovabuilders.ca
andrew@innovabuilders.ca
@InnovaBuilders on Twitter
Innova Builders on Facebook

De-mystifying heating systems

By now, I’m sure you’ve heard or seen numerous ads touting some miracle radiant heater or special pellet stove that will “slash your heating bill by 50%!”…or something similar. Lots of claims about how efficient the heating system is and how much money it will save you.

The plain truth is that how much money, and energy, any heating system will use is mostly dependent on the building itself and how efficient it is, or isn’t (see my previous post on the building envelope). Try putting your car heater on full blast with your windows down on a day like today (-30 wind chills) and you get the picture – it doesn’t matter how much heat the system puts out if you can’t keep the heat in.

For the purposes of this discussion, let’s assume we start with building you a very efficient home. The choice of heating system could be oil, natural gas, wood/pellet, electric, solar-assisted, air-source heat pump or geothermal heat pump, or perhaps a combination. In all cases, passive-solar design features should be incorporated into the house as much as possible to harvest this free heat. We’ll also assume you’re building a house that is, say, 2500-3000sf in total (if we’re truly searching for efficiencies, smaller homes should be considered).

Let’s dispense with oil right out of the gate. Personally, I won’t install it in a home; it has too much environmental disaster potential (anyone remember a recent tank leaking a large amount of oil into a Bedford lake??) and if you’re watching global prices, it’s likely to become extremely expensive in the coming years. Plus, the CO2 emissions from extracting, processing, transporting and burning the oil are huge. Natural gas is far cleaner than oil, is more efficient and does not require a tank. It is, however, still a petroleum product that has to be extracted, processed and shipped to be burned…and is limited in its availability.

Wood and wood pellets are less common as a main heating system, however can be used in a main furnace in conjunction with the forced-air circulation system that is now required in all new construction. There’s a lot more work involved in splitting (if you choose to), stacking, storing, moving and cleaning up after the wood (or pellets)…and you have to be there every day to keep the furnace stoked, but for those who prefer to do that, and have access to the wood (it is a renewable resource), then it can be a viable option.

Electric heat, via a boiler for radiant heat or from baseboards, was commonly used in the past, however is waning in use due to its percieved costs and the fact that if it is your main heat source, you no longer qualify for most of the rebate programs out there for efficient housing. Even though we have an ongoing shift to increased renewable electricity in Nova Scotia, I still agree that electricity should not be the primary heat source.

All of the above sources suffer from one common drawback. They cannot ever achieve above 100% efficiency, and by that I mean produce more than 1 unit of energy for every unit of energy you feed into the system. You may get as high as 90-95% at best, yet it is still always more energy in than out. Remember that every system is still drawing electric power to run fans, burners and any associated equipment…and the fossil fuels (with perhaps the exception of wood) caused more energy to be burned off getting to you from start to finish than they possess when you finally get to burn them. That part is scary.

That leaves us with what I believe to be the best options; solar, air-source heat pumps and geothermal heat pumps. Solar panels can be used for pre-heating domestic hot water, for pre-heating air, and for providing electricity. Relying on solar for most of your heat is possible with a very good design, building orientation and high-performance envelope. Be sure you have some expert advice as this is not for amateurs. The beauty of solar is that once you have the system in place, you’re not “buying” energy from any source to provide heat, so you can achieve more than 100% efficiency (you still need electricity to run fans, etc.). As long as the sun is there, the heat will be there.

Heat pumps have become very popular, and for good reason. Even though you need electricity to run the compressor and fans, it actually produces more energy that it uses – from 300% to as much as 520% efficiency, with the geothermal systems being on the higher end. Air source heat pumps provide both heating and cooling (you simply reverse the system to cool in summer – it works on the same principle as your refrigerator) so you get both features with one system – none of the other systems can do this. The real gem is the geothermal heat pump systems; they provide not only heating and cooling (at a higher efficiency than the air-source units), but also pre-heat your domestic hot water so less energy is needed to bring it up to the temperature you want at your taps and shower. Even better is that during summer with the system is in cooling mode, all the heat it extracts from the air inside the home gets transferred into the hot water pre-heat tank so that very little energy is needed to use the water at your taps/showers. It’s a real all-in-one system that has the free energy of the earth available 24/7 regardless of weather conditions, time of day or time of year.

Of course cost is a consideration. Of the systems I choose as the best, the air-source heat pump would be the lesser priced to install with the solar and geothermal systems being a bit more, though also deliver the best bang-for-the-buck in the long run. All are very efficient and you can’t really go wrong with any of them. Actually, let’s not use the term “cost” and call it “investment“, since that’s exactly what it is…an investment in your home that produces enormous savings in purchased energy. And that helps our communities stay cleaner as well as lower your costs and add significant value to your home. Ten years from now when someone is looking to buy a house, they will be looking most favourably at the ones that use the least energy. Want yours to be at the top of the list?

Remember that when you build a high-performance envelope around the house, and incorporate good design elements, your system really does not have to work very hard to keep you warm, or cool. So invest in good construction so that your operating costs are kept very low, and stable, and see both the savings grow over time as well as your re-sale value.

As always, please do provide your questions and comments.

Andrew W. Alcorn, CET
Innova Builders, Inc.
www.innovabuilders.ca
andrew@innovabuilders.ca

Andrew is a member of the Halifax Chamber of Commerce Energy Advisory Group
and the Canada Green Building Council (Atlantic Chapter) Residential Committee

The building envelope – The most important factor in energy savings

You hear it talked about – the “envelope” of your home. But what is it?

The envelope is comprised of the foundation walls, basement floor slab (or ground-level floor slab if no basement), exterior walls, windows and doors, and the top floor ceiling. These are the areas of living space that are exposed to outside air or the ground, and are the surfaces that leak heat, air and moisture either in, or out, of your home. Regardless of how “efficient” your heating system may be, if the envelope does not seal off air flow and insulate properly, you’re wasting huge amounts of energy, and money. On top of that, the comfort level of your home will be very difficult to control.

Newer homes are built with better air-sealing characteristics in order to meet building code standards, and are (usually) built with higher levels of insulation. Often, the airflow is not blocked from entering the wall cavities, but does get stopped at the back of the drywall against the plastic vapour barrier – this still causes much heat loss, even though air leakage into the interior of the house is kept to a minimum. Older homes tend to have poor insulation levels and even poorer air-sealing, giving them an even larger potential for energy savings.

Let’s start with what can be done with new construction. Opinions differ on what the “best” construction methods are, and there are several options for very efficient buildings, with varying price tags attached to them depending on just how far you want to take things. Whether you build to Passive House standards,  use ICFs, or my InnovaWall system, keeping outside air out of the envelope and having a high level of properly installed (and I can’t stress that part enough) insulation are critical to ensuring your house uses little energy to heat it. Passive solar features should always be incorporated as much as possible to utilize the free energy from the sun, basements should be insulated on the outside to allow the concrete to act as a heat sink, and the combination of all these features means your heating/cooling system needs to do very little to keep you warm or cool. Of course in all cases, a properly designed and balanced (again, cannot stress this enough) HVAC system with a high-efficiency heat-recovery ventilator is required to ensure fresh air circulation and comfort.

When it comes to existing homes, especially older ones, creating major energy, and comfort, savings requires some renovation work. We often see people replacing their windows, doors and siding all at once on an older home and this is a prime opportunity to upgrade the insulation and air-sealing of a large portion of the home`s envelope. By furring out the new siding a couple of inches, this creates a void that can be filled with closed-cell sprayfoam insulation which is extremely good at sealing air leaks and providing a significant insulating value, even in just a 2″ layer. I have seen many homes with rigid styrofoam insulation boards added at some point, yet the house is still cold. Why? – because they did not seal off airflow from getting under, around or behind it. Once you allow airflow by, you just wasted your money on that insulation.

Because it is such a great insulator, vapour barrier and air-seal, closed-cell sprayfoam is also ideal for those basements and ceilings you’re looking to upgrade the insulation on…just be sure you have taken care of any water leakage first.

These are the basics, and there are many details involved in complete installations, so please send along your questions or comments on this topic.

Andrew W. Alcorn, CET
Innova Builders
www.innovabuilders.ca
andrew@innovabuilders.ca

Andrew is a member of the Halifax Chamber of Commerce Energy Advisory Group
and the Canada Green Building Council (Atlantic Chapter) Residential Committee

%d bloggers like this: